Privacy concerns relating to sharing network traces have traditionally been handled via sanitization, which includes removal of sensitive data and IP address anonymization. We argue that sanitization is a poor solution for data sharing that offers insufficient research utility to users and poor privacy guarantees to data providers. We claim that a better balance in the utility/privacy tradeoff, inherent to network data sharing, can be achieved via a new paradigm we propose: secure queries. In this paradigm, a data owner publishes a query language and an online portal, allowing researchers to submit sets of queries to be run on data. Only certain operations are allowed on certain data fields, and in specific contexts. Query restriction is achieved via the provider's privacy policy, and enforced by the language's interpreter. Query results, returned to researchers, consist of aggregate information such as counts, histograms, distributions, etc. and not of individual packets. W...